diff --git a/src/err.ts b/src/err.ts
index 4283ec0..9183bea 100644
--- a/src/err.ts
+++ b/src/err.ts
@@ -1,6 +1,8 @@
 // notableErrors is a persistent list of errors that should be checked after
 // testing. You should only add to this array in the event of an error that
 // indicates a bug with the kernel.
+import { OpenQueryResponse } from "./queries.js";
+
 const notableErrors: string[] = [];
 
 // respondErr will send an error response to the caller that closes out the
@@ -13,6 +15,7 @@ function respondErr(
   event: MessageEvent,
   messagePortal: any,
   isWorker: boolean,
+  isInternal: false | ((message: OpenQueryResponse) => void),
   err: string,
 ) {
   const message = {
@@ -20,9 +23,11 @@ function respondErr(
     method: "response",
     data: {},
     err,
-  };
-  if (isWorker === true) {
+  } as OpenQueryResponse;
+  if (isWorker) {
     messagePortal.postMessage(message);
+  } else if (isInternal) {
+    isInternal(message);
   } else {
     messagePortal.postMessage(message, event.origin);
   }
diff --git a/src/message.ts b/src/message.ts
index e5de5ce..5ef74b6 100644
--- a/src/message.ts
+++ b/src/message.ts
@@ -83,6 +83,7 @@ export const handleIncomingMessage = function (event: any) {
         event,
         event.source,
         false,
+        false,
         "caller is an extension, but not domain was provided",
       );
       return;
@@ -106,6 +107,7 @@ export const handleIncomingMessage = function (event: any) {
     event,
     event.source,
     false,
+    false,
     "unrecognized method: " + event.data.method,
   );
 };
diff --git a/src/queries.ts b/src/queries.ts
index 1538478..b43f362 100644
--- a/src/queries.ts
+++ b/src/queries.ts
@@ -53,7 +53,7 @@ interface OpenQuery {
   origin: string;
 }
 
-interface OpenQueryResponse {
+export interface OpenQueryResponse {
   nonce: string;
   method: string;
   data: any;
@@ -96,7 +96,7 @@ function handleWorkerMessage(event: MessageEvent, mod: Module, worker: Worker) {
   // Perform input verification for a worker message.
   if (!("method" in event.data)) {
     logErr("worker", mod.domain, "received worker message with no method");
-    respondErr(event, worker, true, "received message with no method");
+    respondErr(event, worker, true, false, "received message with no method");
     return;
   }
 
@@ -113,6 +113,7 @@ function handleWorkerMessage(event: MessageEvent, mod: Module, worker: Worker) {
         event,
         worker,
         true,
+        false,
         "received log messsage with no data field",
       );
       return;
@@ -127,6 +128,7 @@ function handleWorkerMessage(event: MessageEvent, mod: Module, worker: Worker) {
         event,
         worker,
         true,
+        false,
         "received log messsage with no message field",
       );
       return;
@@ -144,6 +146,7 @@ function handleWorkerMessage(event: MessageEvent, mod: Module, worker: Worker) {
         event,
         worker,
         true,
+        false,
         "received log messsage with invalid isErr field",
       );
       return;
@@ -169,7 +172,7 @@ function handleWorkerMessage(event: MessageEvent, mod: Module, worker: Worker) {
       "worker sent a message with no nonce",
       event.data,
     );
-    respondErr(event, worker, true, "received message with no nonce");
+    respondErr(event, worker, true, false, "received message with no nonce");
     return;
   }
 
@@ -319,6 +322,7 @@ async function handleModuleCall(
       event,
       messagePortal,
       isWorker,
+      isInternal,
       "moduleCall is missing 'module' field: " + JSON.stringify(event.data),
     );
     return;
@@ -349,6 +353,7 @@ async function handleModuleCall(
       event,
       messagePortal,
       isWorker,
+      isInternal,
       "'module' field in moduleCall is expected to be a raw CID or a resolver CID",
     );
     return;
@@ -362,6 +367,7 @@ async function handleModuleCall(
       event,
       messagePortal,
       isWorker,
+      isInternal,
       "no 'data.method' specified, module does not know what method to run",
     );
     return;
@@ -376,6 +382,7 @@ async function handleModuleCall(
       event,
       messagePortal,
       isWorker,
+      isInternal,
       "'data.method' needs to be a string",
     );
     return;
@@ -389,6 +396,7 @@ async function handleModuleCall(
       event,
       messagePortal,
       isWorker,
+      isInternal,
       "presentSeed is a privileged method, only root is allowed to use it",
     );
     return;
@@ -399,6 +407,7 @@ async function handleModuleCall(
       event,
       messagePortal,
       isWorker,
+      isInternal,
       "no field data.data in moduleCall, data.data contains the module input",
     );
     return;
@@ -414,6 +423,7 @@ async function handleModuleCall(
         event,
         messagePortal,
         isWorker,
+        isInternal,
         "registry entry for module is not found",
       );
     };
@@ -511,6 +521,7 @@ async function handleModuleCall(
           event,
           messagePortal,
           isWorker,
+          isInternal,
           addContextToErr(errML, "module could not be loaded"),
         );
         return;
@@ -530,7 +541,7 @@ async function handleModuleCall(
     const [moduleData, errDS] = await downloadSmallObject(finalModule);
     if (errDS !== null) {
       const err = addContextToErr(errDS, "unable to load module");
-      respondErr(event, messagePortal, isWorker, err);
+      respondErr(event, messagePortal, isWorker, isInternal, err);
       resolve(err);
       delete modulesLoading[moduleDomain];
       return;
@@ -563,7 +574,7 @@ async function handleModuleCall(
     const [mod, errCM] = await createModule(moduleData, moduleDomain);
     if (errCM !== null) {
       const err = addContextToErr(errCM, "unable to create module");
-      respondErr(event, messagePortal, isWorker, err);
+      respondErr(event, messagePortal, isWorker, isInternal, err);
       resolve(err);
       delete modulesLoading[moduleDomain];
       return;
@@ -605,7 +616,7 @@ function handleModuleResponse(
   if (!(event.data.nonce in queries)) {
     // If there's no corresponding query and this is a response, send an
     // error.
-    if (isResponse === true) {
+    if (isResponse) {
       logErr("worker", mod.domain, "received response for an unknown nonce");
       return;
     }